Automotive devices such as transmissions, both automatic and standard which use recirculating-transmission fluid, as well as internal combustion engines which use recirculating lubricating oil, filter the fluid and oil to remove particulate contaminants therefrom. In these devices, oil drains into oil pans prior to being recirculated through the transmission or engine. In automatic transmissions, it is a practice to use a pan-type filter with a flow tube covered by a pan/tray with the tray acting as a sump for the fluid. Some sumps have a horizontal floor and others have an inclined floor. The filter life is determined by the area of the media and by utilization of the media in a way that provides good flow characteristics.
In order to decrease the cost of transmission maintenance by protecting the quality of the oil used as transmission fluid, there is a need to increase the life of the filter media, while improving efficiency and decreasing restriction thereof.